ACOUSTIC SURFACE WAVE ELEMENT AND DEVICE

摘要

PROBLEM TO BE SOLVED: To provide an acoustic surface wave element and an acoustic surface wave device with the element mounted, the element having improved durability provided with an IDT electrode which, while having an electrode finger with a plurality of conductor layers stacked, can suppress occurrence of fracture or peeling in these conductor layers. SOLUTION: The acoustic surface wave element 1 includes the IDT electrode 11 having an electrode finger 11a on a piezoelectric substrate 10. The electrode finger 11a is formed by stacking an intermediate layer 12 and an electrode layer 13 having a thermal expansion coefficient larger than that of the intermediate layer 12. The electrode finger 11a has a trapezoidal cross section becoming wider as it goes closer to the piezoelectric substrate 10. An angleα1formed by a side plane 1 of the intermediate layer 12 is larger than an angleβ1formed by a side plane of the electrode layer 13. COPYRIGHT: (C)2008,JPO&INPIT